The present invention relates to a motor driving device and a motor system, and relates to the technology which is useful for adjusting the phase of a drive current of a motor as an example.
Patent Literature 1, for example, discloses a system to calculate the phase of a drive voltage of a motor based on an arithmetic expression which employs an angular frequency, a drive current value, and characteristic constants (a torque constant and an impedance value) of the motor. Patent Literature 2 discloses a system in which one of the phase of a back electromotive force and the phase of a drive current is selected to control the energization timing of a motor.
(Patent Literature 1) Japanese Unexamined Patent Application Publication No. 2010-288396
(Patent Literature 2) Japanese Unexamined Patent Application Publication No. 2005-102447